Chap. VI. LEDGES ON HILL-SIDES. 281 



the inland side of Beacliy Head, where the 

 surface sloped at about 25°, many short little 

 embankments like those just mentioned. 

 They extended horizontally and were from a 

 few inches to two or three feet in length. 

 They supported tufts of g7-ass growing 

 vigorously. The average thickness of the 

 mould of which they were formed, taken 

 from nine measurements, was 4*5 inches; 

 while that of the mould above and beneath 

 them was on an average only 3*2 inches, and 

 on each side, on the same level, 3*1 inches. 

 On the upper parts of the slope, these em- 

 bankments showed no signs of having been 

 trampled on by sheep, but in the lower parts 

 such signs were fairly plain. No long con- 

 tinuous ledges had here been formed. 



If the little embankments above the Cor- 

 niche road, wliich Dr. King saw in the act 

 of formation by the accumulation of dis- 

 integrated and rolled worm-castings, were to 

 become confluent along horizontal lines, ledges 

 would be formed. Each embankment would 

 tend to extend laterally by the lateral extension 

 of the arrested castings; and animals grazing on 

 a steep slope would almost certainly make use 



